You mean like fighter, cleric, thief, magic-user, and elf? And the cooldowns are there to encourage you to use multiple powers - as opposed to 3.x, where the standard wizard spell selection was fireball, fireball, fireball, bigger fireball, hotter fireball, fireball rules with the damage type switched out for acid, delayed blat fireball, fireball with longer range and the damage type switched to cold, moronically rolling fireball, etc., etc

Each and everyone of those classes can perform very different roles, depending on the player managing them. Combat mages, melee based clerics, ranged fighters, acrobat rogues, necromancer wizards.

If you need cool downs in your rule set to help your players find some variety, then your players are terribly unimaginative, or your DM is. Try having a wizard memorize nothing but fireball and any competent DM will punish him with fire immune creatures, counter spelling enemy wizards, anti magic zones, wild magic zones or a well placed silenced cross bow bold to his torso. Try being creative and not letting your players go full munchkin on you. There is a reason there is a vast array of spells available.

Dungeons and Dragons is not difficult to learn, but is complicated enough to provide the clever and imaginative player with endless hours of play. It doesn't need to be simplified and dumbed down as that can be done by each group according to their wants and needs. If you want simple and straightforward, don't allow extra source books beyond the dungeon master;s guide, player's handbook and monster manual.

Still play it at least once a year for a good three-month campaign. Nothing else comes close to how well they combined modern age with high fantasy.

/Memorable plots: Protecting an ArchLich (the Lawful Good kind) running for President from his opponent, who was a member of Tyr's Sect. We failed.

I ran a campaign where the Stock Exchange was being magically hacked by a high-level Cybermage. The party took him out in two sessions.

UNK (United Nations and Kingdoms) peacekeeping duties in Nuallia (the country ran by Drow and under near-constant power struggles and upheaval) which resulted in having them have to fight off a near-full-powered Lolth trying to enter the world. Two made it out alive.

Guarding a set of 13 books from a series of assaults by mercenaries and covert forces, under strict rules not, NOT to open the chest they were in. End of the campaign we finally met who was paying us and what the books were: The Tomes of Fistandantilus. Raistlin was trying to amass power to take down Elminster for control of The University of Thaumaturgical Sciences.

Fighting a group of Frost Giants in the Northwest Territories.

The looks on our faces when our INT 7 Ranger decided to acquire a totem animal (who actually became the most bad-ass NPC we had in our party): A pound animal named "Kitty". "Kitty" was a Displacer Beast. We told him that was a "bad Kitty" and were scolded for being jerks and 'cat-haters'. "Kitty" (Khaitti) wound up saving our asses twice. The way it talked, though, was the clincher of having it stay for combat and entertainment value: "HUMAN! I demand a belly-rub!", "I. DO. NOT. EAT. CHEESEBURGERS!", "DAMMIT! YOU STUPID HUMANS! How did you fall for THAT?! Now, excuse me, someone has left me a plate of Bluefin as appeasement... ::thud:: ::snoooore:::"

Having our U.S. Templar (see: Marine) wind up discovering an old Vietnam-era M-16, and being forced to grab and use it after his ran out of ammo - and watching a 20th Century Holy Avenger take out four ogres in reactive armor. (Not as cool as the inscription the DM put on the stock: "A hero's strength comes not from anger, but from defiance.")

Going toe-to-toe with a Chromatic Red Great Wyrm on The Strip in Las Vegas. That was the last one we played a few months ago.A character who played a Lawful Good Illithid... who worshipped Cthulhu."Really! It'll be better! No more pain or suffering, we all get to stop fighting among each other! How is that BAD?!""Well, for one, we're ALL DEAD."He also had to buy his food off of the Internet, mainly cow brains.